1. Field of the Invention
The present invention relates to a reading apparatus, a reading method, a program, and a program recording medium. More particularly, the present invention relates to a reading apparatus for reading content, a reading method, a program, and a program recording medium.
2. Description of Related Art
FIG. 1 is a block diagram showing the configuration of a recording and playback system of related art.
A video/audio encoder 11 encodes image data of a baseband corresponding to an input image signal in accordance with the MPEG (Moving Pictures Experts Group) system. Furthermore, the video/audio encoder 11 encodes audio data of a baseband corresponding to an input audio signal (not shown) in accordance with the MPEG system. The video/audio encoder 11 supplies data obtained by the encoding to a stream encoder 12.
The stream encoder 12 multiplexes the encoded data, which is supplied from the video/audio encoder 11, converts the data into a stream by an MPEG transport stream method or an MPEG program stream method, and supplies the data stream obtained by the conversion to a write buffer 13.
The write buffer 13 temporarily stores the data stream supplied from the stream encoder 12 and supplies the stored data stream to a drive 14.
The drive 14 records the data supplied from the write buffer 13 onto a loaded optical disc 15. Furthermore, the drive 14 reads data that is recorded as a file from the loaded optical disc 15, and supplies the read data to a read buffer 19.
A juke system 16 controls loading and unloading of the optical disc 15 into and from the drive 14. The juke system 16 allows a picker 18 to select one of the optical discs 15 from disc slots 17 that store each of a plurality of optical discs 15.
Under the control of the juke system 16, the picker 18 transports the selected optical disc 15 and allows it to be loaded into the drive 14. Under the control of the juke system 16, the picker 18 transports the optical disc 15 taken out from the drive 14 and allows it to be stored in one of disc slots 17, that is, the juke system 16 controls the picker 18.
The read buffer 19 includes a semiconductor memory or a hard disk, and temporarily stores a data stream supplied from the drive 14. The read buffer 19 absorbs reading jitter, flattens the data rate so as to become constant, and supplies the stored data stream to a stream decoder 20.
The stream decoder 20 separates the data stream by the MPEG transport stream method or the MPEG program stream method into image data and audio data, and supplies the separated image data and audio data to a video/audio decoder 21.
The video/audio decoder 21 decodes the encoded image data and audio data into image data and audio data of a so-called baseband. Furthermore, the video/audio decoder 21 supplies, to a monitor 22, the output image signal and audio signal (not shown) based on the image data and audio data of the baseband, respectively, which are obtained by the decoding.
The monitor 22 displays an image on the basis of the output image signal and outputs audio on the basis of the supplied audio signal.
A description will now be given, with reference to FIG. 2, of a playback process of the recording and playback system. At time t0, when playback is requested from a user, the optical disc 15 on which data of content for which playback is requested is transported by the picker 18 from the disc slot 17 to the drive 14. At time t1, the optical disc 15 is loaded in the drive 14.
At time t2, reading of data recorded on the loaded optical disc 15 is started, and the data is stored in the read buffer 19. At time t3, when a predetermined amount of data is stored in the read buffer 19, the data stored in the read buffer 19 is read into the stream decoder 20. Then, the video/audio decoder 21 decodes the image data and the audio data, and supplies an output image signal and an output audio signal corresponding to the image data and the audio data obtained by the decoding to the monitor 22. At time t4, on the basis of the output image signal and the output audio signal, the monitor 22 displays an image and outputs audio.
That is, from when playback is requested from the user at time t0 until an image is displayed on the monitor 22 at time t4, a time lag corresponding to the period of time necessary from when the optical disc 15 stored in the disc slot 17 is loaded into the drive 14 until image data is read from the loaded optical disc 15 occurs. This time lag is approximately 20 to 30 seconds depending on the configuration of the recording and playback system.
This time lag occurs each time playback is requested. As a consequence, the user may feel very anxious. This point is a serious problem from the viewpoint of ease of operation.
Accordingly, in the related art, there has been developed a video recording and playback apparatus for recording or reproducing a video and/or audio signal onto or from a first recording medium; a second recording medium having an access time shorter than that of the first recording medium and into or from which a signal from the beginning portion of the video and/or analog signal up to a predetermined period of time is recorded or reproduced when a desired video and/or analog signal is recorded into or from the first recording medium; and a control for controlling the recording and playback means and the second recording medium (for example, refer to Japanese Unexamined Patent Application Publication No. 1997-161461).